cannot pass array in a function javascript

Question

I'm learning javascript and I want to fill an array in one function and pass it as a parameter in the second function. I have the following code but for some reason it is not working.

function gameplay(tmp) {
    for (var i = 0; i < tmp.length; i++) {
        if (xTrans >= tmp[0] - 1
            && xTrans < tmp[0]
            && zTrans <= tmp[1] - 1
            && zTrans > tmp[1])
        {
            //some code here
        }
    }
}

function fillMap() {
    var bounds = new Array();
    for (var y = 0; y < map.length; y++) {
        for (var x = 0; x < map[0].length; x++) {
            if (map[y][x] == '1') {
                bounds[length] = 4 * x;
                length++;
                bounds[length] = -y - 4 * y;
                length++;
            }
        }
    }
    return bounds;
}

and I call like this:

var tmp = fillMap();
gameplay(tmp);

Thanks in advance..

Answer 1

You might want to try this just to confirm what happens when you have a clear and obvious input:

function fillMap() {
var map = [[0]];

That should give you the output of: [4, -5]

Some potential issues

• map isn't defined anywhere
• length isn't defined anywhere
• xTrans is not defined anywhere
• zTrans is not defined anywhere

• It seems unlikely, based on what I see, that the if condition can be met:

  xTrans >= tmp[0]-1 && xTrans < tmp[0] // translates to if xTrans == tmp[0] - 1

Some other thoughts

• You're better off using bounds.push instead of bounds[length] = $val
• for(var y=0; y<map.length ;y++) { for(var x=0; x<map[0].length ;x++) { would be safer/faster as var yLen = map.length; var xLen = map[0].length; for(var y=0; y<yLen ;y++) { for(var x=0; x<xLen ;x++) {
• bounds[length] = -y - 4 * y is the same as bounds[length] = -5 * y;

Answer 2

From you comment it seems that array is not being filled as you have some condition to fill array . So first check you condition is being full filled or not.